Pram is the short form of perambulator, which is a wheeled baby carrier that is designed in such a way that your baby can sleep in it. It has a flat, cushioned base where you can place your baby in the lying position. The wide canopy attached to the rear of the carriage can be pulled to cover more than half of the carriage. This keeps your baby is in a cozy, safe from dust, heat, and rain.This is generally preferred for small babies from 0 to 6 months.

A stroller is designed such that your baby can sit upright. It has safety equipment, such as harness and safety belts, to ensure that your baby is safe sitting inside. A stroller is preferred for infants who have begun to sit. As you can see, a stroller also comes with a hood or a canopy just like a pram.

Pram: Prams are a very convenient means for transporting babies. They can be used right from birth by babies who cannot sit up on their own until later and is often shaped like a basket. They are much heavier than strollers so often bulky if travelling by public transport.Stroller (Pushchair): Stroller or Pushchair as the name suggests is a push chair. Hence it can be used by slightly older babies as the babies can just sit and not lie down.
Hence they are lighter than a pram.